Collar system for a dust extractor

ABSTRACT

A collar system for a dust extractor is provided including: a collar including a drill passage extending through the collar and an extension forming an internal passage that connects at one end with the drill passage, the extension being attachable to a housing of the dust extractor to enable the internal passage to connect to a suction passage of the dust extractor; and a cover mounted adjacent an entrance of the drill passage, the cover being moveable between a first position where it covers the entrance and a second position where is remote from the entrance, wherein the cover comprises at least hole that passes through the cover.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.16/715,341, filed Dec. 16, 2019, which claims priority, under 35 U.S.C.§ 119, to UK Patent Application No. 19 095 31.4 filed Jul. 2, 2019.

FIELD

The present invention relates to a dust extractor for use with a drill,hammer drill or hammer, a system which uses such a dust extractor, andto a method of using such a dust extractor.

BACKGROUND

U.S. Pat. No. 4,205,728, DE202008008561, EP2335869, and EP2474385 alldisclose suction cup dust extractors for use with a drill, hammer drillor hammer. Suction cup dust extractors are located on and attached tothe surface to be drilled or chiseled by a suction force generatedduring the operation of the suction cup dust extractor.

EP1245330, EP1459842, DE10 2007000826A1 and EP2174749B1 disclose dustextractors intended to be mounted on and attached to the drill, hammerdrill or hammer.

US2009/0288682 discloses a collar system having a collar which comprisesa drill passage extending through the collar and an extension forming aninternal passage that connects at one end with the drill passage. Theextension is capable of attaching to the housing of a dust extractor toenable the internal passage to connect to a suction passage of the dustextractor.

SUMMARY

The present invention aims to provide a system, dust extractor andmethod for a dust extractor by which any holes created by a drill,hammer drill or hammer whilst using the dust extractor are cleaned.

Accordingly, there is provided a collar system for a dust extractorincluding a drill passage extending through the collar and an extensionforming an internal passage that connects at one end with the drillpassage. The extension is capable of attaching to the housing of a dustextractor to enable the internal passage to connect to a suction passageof the dust extractor. In an embodiment, there is provided a moveablecover mounted adjacent an entrance of the drill passage capable of beingmoved between a first position where it covers the entrance and a secondposition where is remote from the entrance, wherein the cover comprisesa hole passing through the cover.

BRIEF DESCRIPTION OF THE DRAWINGS

Preferred embodiments of the present invention will now be described, byway of example only and not in any limitative sense, with reference tothe accompanying drawings in which:

FIG. 1 shows a perspective view of the top of a dust extractor accordingto an example of a suction cup extractor;

FIG. 2 shows a top view of the suction cup dust extractor;

FIG. 3 shows a bottom view of the suction cup dust extractor;

FIG. 4 shows a front view of the suction cup dust extractor;

FIG. 5 shows a vertical cross-sectional view of the suction cup dustextractor in the direction of Arrows A in FIG. 4 ;

FIG. 6 shows a perspective view of the underside of the suction cup dustextractor;

FIG. 7 shows a horizontal cross-sectional view of the suction cup dustextractor in the direction of Arrows C in FIG. 4 .

FIG. 8 shows a perspective view of the top of the suction cup dustextractor according to a second example of a suction cup dust extractor;

FIG. 9 shows a top view of the suction cup dust extractor;

FIG. 10 shows a bottom view of the suction cup dust extractor;

FIG. 11 shows a front view of the suction cup dust extractor;

FIG. 12 shows a vertical cross-sectional view of the suction cup dustextractor in the direction of Arrows G in FIG. 11 ;

FIG. 13 shows a horizontal cross-sectional view of the suction cup dustextractor in the direction of Arrows H in FIG. 11 ;

FIG. 14 shows a vertical cross-sectional view of the suction cup dustextractor in the direction of Arrows I in FIG. 12 ;

FIG. 15 shows a close-up view of the venture passages;

FIG. 16 shows a vertical cross section of a dust extractor in accordancewith a third example of a suction cup dust extractor;

FIG. 17 shows a vertical cross section of the dust extractor in thedirection of Arrows A shown in FIG. 16 ;

FIG. 18 shows a vertical cross section of the dust extractor in thedirection of Arrows B shown in FIG. 16 ;

FIG. 19 shows a vertical cross section of the dust extractor in thedirection of Arrows C shown in FIG. 16 ;

FIG. 20 shows an underside view of the dust extractor of FIG. 16 ;

FIG. 21 shows a perspective top view of a dust extractor in accordancewith a first embodiment of the present invention;

FIG. 22 shows a top view of the dust extractor of FIG. 21 ;

FIG. 23 shows a vertical cross-sectional view of the dust extractor ofFIG. 21 ;

FIG. 24 shows a bottom view of the dust extractor of FIG. 21 ;

FIG. 25 shows the collar of the dust extractor of FIG. 21 ;

FIG. 26 shows a perspective view of the pivotal cover of the dustextractor of FIG. 21 ;

FIG. 27 shows a vertical cross-sectional view of the pivotal cover ofthe dust extractor of FIG. 21 ;

FIG. 28 shows the dust extractor with pivotal cover with the pivotalcover in an open position;

FIG. 29 shows the dust extractor with the pivotal cover with the pivotalcover in a closed position;

FIG. 30 shows a dust extractor which mounts onto a hammer drill;

FIG. 31 shows a perspective top view of a collar and pivotal cover inaccordance with a second embodiment of the present invention;

FIG. 32 a shows an air compressor;

FIG. 32 b shows a gas cylinder;

FIG. 32 c shows a dust extractor and vacuum cleaner where the vacuum issucking air from the dust extractor and redirecting the air expelled bythe vacuum cleaner back towards the dust extractor; and

FIG. 32 d shows a brush.

DETAILED DESCRIPTION

Two embodiments of the invention will now be described with reference toenclosed drawings.

Whilst the examples and embodiments of the present invention aredescribed in relation to suction cup dust extractors, it will beappreciated that the invention covers all types of dust extractors.

Referring to FIGS. 1 to 7 , a first example of a dust extractor will nowbe described. The dust extractor is a suction cup dust extractor.

The suction cup dust extractor comprises a housing 10 and a drill collar12 rigidly connected to it at the top end of the housing 10. The housing10 comprises a skirt 14 with a bridge 16 formed on top of the skirt 14.The bridge 16 extends from the middle of the skirt 16 to the top end ofthe skirt 16 where it is attached to the side of the drill collar 12.The skirt 14 has a top wall 50 and side walls 52 which define a largerecess 38, on the opposite side of the skirt 14 to that on which thebridge 16 is attached, which has an opening which faces away from thebridge 16.

The drill collar 12 forms a drill passage 18 which enables a cuttingtool, such as a drill bit (not shown), to pass through it (direction ofArrow B in FIG. 5 ) to engage a work piece 20. The drill collar 12 has alongitudinal axis 22. Both the drill passage 18 and the opening of therecess 38 are orientated in the same direction.

Formed in end 26 of the bridge 16 in the middle of the skirt 14 is anaperture 24 which provides an air exit. The aperture 24 has alongitudinal axis 28 which is perpendicular to and intersects with thelongitudinal axis 22 of the drill collar 12.

Formed by an internal wall 30 of the housing 10 is a first passage 32which extends from the aperture 24 towards the drill passage 18 of thedrill collar 12. The internal wall 30 also forms one of the walls whichform the recess 38. Formed within the first passage 32 is a throat 34where the diameter of the passage 32 is reduced. Two apertures 36 areformed through the wall 30 of the passage 32 at the narrowest point ofthe throat 34. The apertures 36 provide two passageways directly fromthe passage 32, through the wall 30, to the recess 38 formed by theskirt 14. Such a construction provides the operator with easy access tothe apertures 36 should they become blocked with debris as the apertures36 are exposed to the recess which is easily accessible through theopening of the recess 38.

Each of the two apertures 36 has a longitudinal axis 98, which extendsalong the length of the passageway formed by the aperture 36, and whichintersects with the longitudinal axis 100 of the passage 32, at thepoint where the apertures 36 and passage 32 meet, at an angle of between40 and 50 degrees and ideally at 45 degrees (102). The longitudinal axes98 extends into the passage 32 from the apertures 36, in a directionparallel to the longitudinal axis 100 of the passage 32, in the samedirection as the flow of air as it is sucked from the drill passage 18through the passage 32 (direction of Arrow J in FIG. 5 ).

The passage 32 splits into two passages 60 between the throat 34 and thedrill passage 18, each connecting with the drill passage 18 through aseparate aperture 62.

An inlet air passage 64 is formed in by a frame 66 attached to the baseof the drill collar 12 and operates in the same manner as that describedin EP1457288. Air can pass through the inlet air passage into the drillcollar 12 as shown by Arrow D.

A seal 40 locates in a groove 42 formed around the periphery of the wallof the skirt 20 on the underside of the skirt 14. When the suction cupdust extractor is placed against a work piece 20, it engages with theseal 40, the work piece 20 sealing the opening to the recess 38 to forma chamber.

An air hole 68 is provided in the wall 50 of the skirt 20 to provide asmall air passage between the recess and the surrounding atmosphere.During the use of the suction cup dust extractor, the hole 68 ensuresthat there is a limited but constant air flow in the recess formed underthe skirt 20 if the seal provides a perfect air seal with the work piece20.

The suction cup extractor further comprises a tubular connection collar2 which connects to a vacuum source (not shown). A rubber seal 4 isfastened inside of the connection collar 2 and which comprises tworubber rings 4 which extend radially inwards from the drill collar 12with an aperture 8 formed through them. The rings 4 are capable ofgripping onto the nozzle (not shown) of a hose (not shown) of the vacuumsource. As the rings 4 are resilient, they can stretch radiallyoutwardly, increasing the size of the apertures 8, enabling nozzles ofdifferent sizes to be used. The rings 4 would then grip the nozzle dueto their resilience and frictionally hold the nozzle.

The connection collar 2 connects to the aperture 24 via a flexible tube72. One end of the flexible tube 72 is held in a sleeve 74 formed in theconnection collar 2, the other in a sleeve 76 formed in the bridge 16.The flexible tube 72 can be stretched to extend its length and move thecollar 2 away from the housing 10 or be bent or twisted to allow theconnection collar 2 to be moved to a range of positions relative to theaperture 24. The flexible tube 72 is made from rubber.

In use, the suction cup dust extractor is placed against a surface 70 ofthe work piece 20 so that the seal 40 makes contact with it. A chamberis formed when opening of the recess 38, formed by the walls 30, 50, 52,of the skirt 14 is sealed by the surface 70 of the work piece 20. Thesuction device is activated, and air is sucked through the connectioncollar 2, through the flexible tube 72, through the aperture 24, throughthe first passage 32, through the pair of separate passages 60, throughthe apertures 62 and then from the drill passage 18. As air passesthrough the throat 34 of the first passage 32, it speeds up, causing areduced pressure inside of the two apertures 36 due to a venturi effect.This results in the air in the recess 38 to be sucked out through theapertures 36 and into the passage 32. This causes the skirt 14 and hencethe dust extractor, to be attached to the surface 70 due to the suction.The hole 68 ensures that there is a constant flow of air from the hole68, through the recess 38, and then through the two apertures 36. Theoperator can then drill a hole in the surface by passing the drill bitthrough the drill collar 12 and drilling into the surface 70. Any debrisgenerated during the drilling process will be sucked up into the drillpassage 18 and then into passages 60. The use of two passages providesbetter debris clearance. The debris is then transported through thepassage 32, through the aperture 24, through the flexible tube 72 andthen through the connection collar 2. The hole 68 ensures that there isalways air passing through the two apertures into the passage 32, thusensuring no debris passes into the apertures 36 or the recess 38.Furthermore, the 45-degree angle between the apertures 36 and passage 32further reduces the risks of any debris entering the apertures 36 as itsucked past the apertures 36 from the drill passage 18 to the aperture24.

A second example of suction cup dust extractor will now be describedwith reference to FIGS. 8 to 15 . Where the same features are present inthe second example are also present in the first example, the samereference numbers have been used. The design of the second example isthe same as that for the first embodiment except for the design of threefeatures, namely, 1) the design of the seal 40 has been altered, 2) theprovision of an additional aperture to the two apertures 36, and 3) anew feature of a pressure release mechanism for the recess 38 has beenadded.

Firstly, the changes to the design of the seal will be described.

Referring to FIGS. 10, 12, and 14 , the opening 80 of the recess 38 isplanar ie the periphery of the opening 80 locates in a flat plane 82.The seal comprises a base 84 which locates in a groove 42 formed in thewall 52 of the skirt 14. The base 84 of the seal is held within thegrove 42 via cover 90 which is held in place on the housing using screws(not shown). A flange 86 is attached to the base 84 which extends fromthe base 84 in a direction which is an oblique or small angle 88relative to the plane 82. The flange 86 extends, in a direction parallelto the plane 82 (in the direction of Arrows M), away from the opening80. The flange 86 extends, in a direction perpendicular to the plane 82(in the directions of Arrows N), away from the opening 80. The outerperimeter of the flange 86 is supported by a secondary wall 92 formed onthe shirt 14 of the housing 10.

Secondly, the additional aperture 94 and its inter connection with therecess will now be described.

Referring to FIGS. 12, 13 and 15 , in addition to the two apertures 36formed through the wall of the passage 32 at the narrowest point of thethroat 34 to provide two direct passageways from the passage 32 to therecess 38, there is provided a third aperture 94, located between thetwo apertures 36, which is formed through the wall of passage 32 at thenarrowest point 34 and which connects to an intermediary chamber 96formed in the bridge 16. The intermediary chamber 96 connects to therecess 38 so that air can feely move between the intermediary chamber 96and the recess 38. The outer wall of the intermediary chamber is formedby the external wall of the bridge 16.

Each of the two apertures 36 has a longitudinal axis 98, which extendsalong the length of the passageway formed by the aperture 36, and whichintersects with the longitudinal axis 100 of the passage 32, at thepoint where the apertures 36 and passage 32 meet, at an angle of between40 and 50 degrees and ideally at 45 degrees (102). The longitudinal axes98 extend into the passage 32 from the apertures 36, in a directionparallel to the longitudinal axis 100 of the passage 32, in the samedirection as the flow of air as it is sucked from the drill passagethrough the passage 32 (direction of Arrow J in FIGS. 12 and 15 ).

The third aperture 94 has a longitudinal axis 104, which extends alongthe length of the passageway formed by the aperture 94, and whichintersects with the longitudinal axis 100 of the passage 32, at thepoint where the third aperture 94 and passage 32 meet, at an angle ofbetween 40 and 50 degrees and ideally at 45 degrees 106. Thelongitudinal axis 104 extends into the passage 32 from the aperture 94in a direction parallel to the longitudinal axis 100 of the passage 32,in the same direction as the flow of air as it is sucked from the drillpassage through the passage 32 (direction of Arrow J in FIGS. 12 and 15.

The 45-degree angle between the apertures 36 and passage 32 reduces therisks of any debris entering the apertures 36 or third aperture as itsucked past the apertures 36, 94 from the drill passage 18 to theaperture 24.

The addition of the third aperture provides for increased suction in therecess 38.

Thirdly, the new feature of a pressure release mechanism for the recess38 will now be described.

Formed in each side of the bridge 16 is a button aperture 110. Locatedwithin each button aperture 110 is a button 112. Each button 112 ismounted on an end 116 of a flexible plastic support 114 which extendsaround the inside of the outer wall 118 of the bridge 16 inside of theintermediary chamber 96, wrapping around the top half of the passage 32(see FIG. 14 ). A leaf spring 120, which extends along the length of theplastic support 114, is surrounded by the plastic support 114, and alsowraps around the top half of the passage 32. The ends 122 of the leafspring 120 directly engage behind the ends 116 of the plastic supportbehind the buttons 112. The leaf spring 120 is resilient in nature and,if left in isolation would straighten up along its length. When locatedas shown in FIG. 14 , the leaf spring 120 has been bent against itsbiasing force in order to be able to fit in the position as shown. Theends of the leaf spring 120 urge the ends 116 of the plastic supportoutwardly (in the direction of Arrow Q), urging the buttons 112 throughthe apertures 110.

The edges of the ends 116 of the plastic support 114 engage with theedges 124 of the walls of the bridge 16 and skirt 14 housing 10, due tothe biasing force of the spring 120, to seal the apertures 110, thuspreventing any air from escaping from the intermediary chamber 96through the apertures 110.

In use, the suction cup dust extractor is placed against a surface 70 ofthe work piece 20 so that the seal 40 makes contact with it. A chamberis formed when opening of the recess 38, formed by the walls 30, 50, 52,of the skirt 14 is sealed by the surface 70 of the work piece 20. Thesuction device is activated, and air is sucked through the connectioncollar 2, through the flexible tube 72, through the aperture 24, throughthe first passage 32, through the pair of separate passages 60, throughthe apertures 62 and then from the drill passage 18. As air passesthrough the throat 34 of the first passage 32, it speeds up, causing areduced pressure inside of the three apertures 36, 94 due to a venturieffect. This results in the air in the recess 38 to be sucked out eitherdirectly through the two apertures 36 or through the intermediarychamber 96 and the third aperture 94 and into the passage 32. Thiscauses the skirt 14 and hence the dust extractor, to be attached to thesurface 70 due to the suction. During the normal operation, the buttons112 are in their outer most position due to the biasing force of theleaf spring 120, the edges of the ends of the plastic support engagingwith the edges 124 of the of the walls of the bridge and skirt 14. Inorder to release the suction cup extractor from the wall, the operatorhas two options. Firstly, the operation can switch of the vacuum device,reducing the pressure in the recess. Alternatively, the operator candepress the buttons 112, moving the buttons 112 and the ends 116 of theplastic support 114, against the biasing force of the leaf spring 120,into the intermediary chamber 96, breaking the seal formed between theedges of the ends 116 of the plastic support 114 and the edges 124 ofthe of the walls of the bridge 16 and skirt 14, allowing air to besucked in to the intermediary chamber from the air surrounding theextractor. This increases the pressure in the intermediary chamber 96which, in turn, increases the pressure in the recess 38. As such, theamount of suction created within the recess is reduced, allowing theoperator to remove the extractor from the wall.

The use of two button constructed in this manner allows the operator topinch the buttons 112 to release the extractor and support the extractorwhilst only holding the buttons 112.

A third example of a suction cup dust extractor now be described withreference to FIGS. 16 to 20 . Where the same features are present in theembodiment are also present in the second known example described above,the same reference numbers have been used. The design of the embodimentis the same as that for the second example except for the design of theaperture 24, the first passageway 38 and the drill collar 12.

In the second example, the peripheral wall of the housing 10 whichsurrounds the aperture 24 connects to the wall 30 of the housing 10which forms the first passage 32. The first passage 32 extends from theaperture 24 to the drill passage 18 of the collar 12 so that air canflow from the drill passage 18 of the collar 12 to the aperture 24through the first passage 32. Part of the wall 30 of the first passage32 forms part of the wall 30 of the recess 38. The first passage 32connects to the recess through two apertures 36. As such, air can onlypass directly between the recess 38 and the first passage 32 through thetwo apertures 36. Formed in the bridge 16 is an intermediary chamber 96.Part of the wall 30 of the first passage 32 forms part of the wall 30 ofthe intermediary chamber 96. The first passage 32 connects to the recess38 through a third aperture 94. As such, air can only pass directlybetween the intermediary chamber 96 and the first passage 32 through thethird apertures 94. The intermediary chamber 96 and recess are connectedso that air can flow between the intermediary chamber 96 and the recess38. Therefore, air can only flow from the recess 38 and the firstpassage 32 either directly through the two apertures 36 or indirectlythrough the third aperture 94. As such, air can only flow from therecess 38 to the aperture 24 either directly through the two apertures36 or indirectly through the third aperture 94, and then through thefirst passage. As such the amount of the air that can flow from therecess 38 to the aperture is limited by the size of the three apertures36, 94.

In the third example, the aperture 24 is directly connected to therecess 38 and intermediary chamber 96. The part of the wall 30 whichforms the first passage 32 which is located in close proximity to theaperture 24 is formed as a straight tube 802. The tube 802 extendsthrough the aperture 24. The tube 802 extends perpendicularly to theplane of aperture 24 and to the drill passage 18. The diameter of theaperture 24 is greater than that of the tube 802 such that a gap 804 isformed around the tube 802 within the aperture 24. The gap 804 extendsalong the tube 802, between the tube 804 and the wall 806 which formsthe perimeter of the aperture 24, until it engages with the recess 38and the intermediary chamber 96. The gap 804 is in direct fluidcommunication with the recess 38 and intermediary chamber 96, to form asecond air passage, so that air can flow directly from the recess 38 andintermediary chamber 96 through the gap 804 in order to pass through theaperture 24. The tube 804 extends into the end of the flexible tube 72,which connects between the connection collar 2 and aperture 24, with theend terminating inside of the flexible tube 72. The end of the tube 802remote from the drill passage, inside of the flexible tube 72 is freestanding i.e. it does connect to or make contact with any other part ofthe housing.

The intermediary chamber 96 is located above the first passage 32. Therecess 38 is located below the first passage 32. The intermediarychamber 96 extends downwardly around both sides of the first passage 32,including a part of the tube 802, to merge with the recess 38 whichextends upwardly around both sides of the first passage 32, includingthe part of the tube 802, to form a suction chamber 38, 96. As such, thesuction chamber 38, 96 surrounds the part of the tube 802

During the operation of the suction cup dust extractor, the suction cupdust extractor is placed against a surface 70 of the work piece 20 sothat the seal 40 makes contact with it. The suction chamber 38, 96 issealed when opening of the recess 38 is sealed by the surface 70 of thework piece 20. The suction device is activated, and air is suckedthrough the connection collar 2, through the flexible tube 72, throughthe aperture 24, through the first passage 32, through the pair ofseparate passages 60, through the apertures 62 and then from the drillpassage 18. In addition, air is also through the connection collar 2,through the flexible tube 72, through the aperture 24, from the suctionchamber 38, 96. This results in the air in the suction chamber 38, 96 tobe sucked out to hold the suction cup dust extractor to the worksurface. This is in addition to air being sucked out of the recess 38through the two apertures 36 into the first passage 32 and out of theintermediary chamber 96 through the third aperture 94 into the firstpassage 32. As the gap 804 is larger than the three apertures 36, 94,the reduction in air pressure in the suction chamber 38, 96 isincreased.

It will be appreciated by the reader that the three apertures 36, 94 canbe omitted from the design, with all of the air being sucked out of thesuction chamber 38, 96 through the gap 804 only.

The drill collar is releasably detachable to the housing 10 via a latchmechanism. The drill collar 12 can be detached from the housing by thedepression of a button 800. EP2474385 describes such a suction cup dustextractor with a detachable collar.

A first embodiment of the present invention will now be described withreference to FIGS. 21 to 29 . Where the same features are present in thefirst embodiment are also present in the examples described above, thesame reference numbers have been used. The design of the embodiment issimilar to for the examples described above. The new feature of thefirst embodiment is the design of the drill collar 12.

The drill collar 12 is releasably attached to the housing 10 of the dustextractor. The collar 12 is best seen in FIG. 25 and comprises a tubularextension 700 through which extends an internal passage 702. Theinternal passage 702 connects with the drill passage 18 of the collar 12via an intermediate chamber 704 which surrounds the drill passage 18.The tubular extension 700 comprises a flexible tab 706 and a catch 708.The tab 706 can bend in the direction of arrow Q shown in FIG. 25 . Thetubular extension 700 slides into a correspondingly shaped aperture 710formed in the housing 10. When the tubular extension 700 is insertedinto the aperture 710 of the housing 10, the tab 706 bends inwardly asthe catch 708 engages with the wall of the aperture 710 to allow thetubular extension 700 to slide into the aperture 710 until the extension700 is fully inserted into the aperture 710 where the catch 708 alignswith a recess formed in the wall of the aperture 710, the catch 708entering the recess allowing the tab 706 to bend outwardly to revert toits original shape. The catch 708 is held in the recess by theresilience of the tab 706. Whilst the catch 708 is held in the recess,the tubular extension 700 is locked into the aperture 710, thus lockingthe collar 12 to the housing. Whilst the tubular extension 700 is lockedinto the aperture 710, the internal passage 702 connects to the internalsuction passage 32 of the housing 10.

Mounted on the housing 10 is a button 712 which is biased by a spring714 to an outward position. When the button 712 is in its outwardposition, the base of the button 712 faces into the recess. When thebutton 712 is pressed, moving it towards an inner position against thebiasing force of the spring 714, the base of the button 712 enters therecess. When the tubular extension 700 is locked into the aperture 710,the catch 708 is located in the recess 716. In order to release thecatch 708 from the recess 716, the operator depresses the button 712 inorder to move it towards the inner position against the biasing force ofthe spring 714. The base of the button 712 enters the recess and engagesthe catch 708 in order to push the catch 708 out of the recess. Theoperator can then slide the tubular extension 700 out of the aperture710 to remove the collar 12 from the housing 10.

Mounted on the top of the collar 12 at the rear of the collar 12, abovethe tubular extension 700 are two extensions 718 with semi-circularholes 720, each having a side opening 722. The extensions 718 form onehalf of a hinge.

Mounted on the top of the collar 12 is a pivotal cover 724 (as bestshown in FIG. 26 ). The pivotal cover 724 comprises a rigid plasticouter ring 726 which surrounds an inner rubber washer 728 with a hole730 formed through its centre. The outer periphery of the washer 728 isattached to the inner edge of the ring 726.

The washer comprises an inner section 732 with a thickness which isapproximately the same as that of the ring 726. Surrounding the innersection 732 is an outer section 734 which connects between the innersection 732 and the ring 726. The thickness if the outer section 734 inless than the inner section 732. The inner section forms a conicalshaped hole 730. A plurality of radial ribs 736 are formed on the topsurface of the outer section 734 and extend from the inner section 732radially outwardly to the ring 726. The ribs provide support for theinner section 732 when a pipe is passed through the hole 730. Formed onthe underside of the inner section 732 is a conical funnel 738 whichextends the length of the hole 730 formed through the inner section 732.The washer 728 is formed in a one-piece construction.

The washer 728 is integrally molded onto the ring 726.

Mounted on the rear of the pivotal cover 724 is a rod 740 which issupported by four posts 742 which divide the rod 740 into three sections744, 746,748. The posts 742 and the rod 740 are integrally formed withthe outer ring 726. The posts 742 connect to the outer ring 726. The rod740 forms the other half of the hinge. The two outer sections 744, 748are able to be releasably clipped into the semi-circular holes 720 ofthe two extensions 718 to form the hinge. When the rod 40 is clipped inthe semi-circular holes 720, the rod 740 can freely pivot about an axiswithin the semi-circular holes 720 allowing the cover to pivot towardsor away from the collar 12. The axis extends in a direction parallel toa plane of the entrance of the drill passage 18. The pivotal cover 726can pivot from a first position where it covers the top entrance to thedrill passage 18 to a second position where it extends away from thecollar exposing the top entrance to the drill passage 18 of the collar12. The pivotal cover 724 can be removed from the collar 12 byunclipping the rod 740 from the semi-circular holes 720. This allows thecollar to be used without the cover 724.

Mounted on the front of the pivotal cover 724 is a U-shaped catch 750.The U-shaped catch 750 comprises two arms 752 which are attached to theouter ring 726 and which extend, in parallel to each other,perpendicularly to the plane of the pivotal cover 724 and aninterconnecting bar 754 which connects between the two ends of the arms752 remote from the outer ring 726. The arms 752 and the bar 754 areintegrally formed with the outer ring 726. The U-shaped catch 750 isused to lock the cover 726, when clipped onto the collar 12, in itsfirst position where it covers the top entrance to the drill passage 18.

In addition, there is provided a lower cover 758 which clips onto theunderside of the collar 12. The lower cover 758 comprises a lip 760 onone side which is capable of being inserted into a recess within thecollar 12. On the other side there is a lower cover catch 762. To attachthe lower cover 758, the lip 760 is inserted into the recess and thenthe lower cover catch 762, which is resiliently deformable, engages witha ridge 764 formed on the outer wall of the collar 12. The lower cover758 comprises an aperture which aligns with the lower exit end of thedrill passage. Such a lower cover 758 is described in EP2474384.

When the pivotal cover 72 is clipped onto the collar 12 and is in itsfirst position where it covers the top entrance to the drill passage 18,the U-shaped catch 750, which is resilient deformable, locks the cover726 by engaging the lower cover catch 762 which comprises an engagementridge 768. It will be appreciated that as an alternative the U-shapedcatch 750 could be made to engage with the ridge 764 on the outside wallof the collar, thus allowing the collar 12 to be used without a lowercover.

A groove 769 is formed around the inner wall of the drill passage 18adjacent the top entrance of the drill passage 18, the wall of thegroove 768 being form by castellations 770. A circular brush 772comprising an outer ring and bristles which point radially inwardlylocates within the groove 769, the outer ring being held in the groove769 with the bristles extending inwardly covering the top entrance tothe drill passage 18.

The use of the collar with the pivotal cover will now be described withreference to FIGS. 28 and 29 .

The collar 12 is attached to the housing of a suction cup dustextractor. The suction cup dust extractor is attached to a vacuumcleaner 782 via a hose 784 which attaches to the connection collar 2,which is then switched on. The suction cup dust extractor is them placedagainst a surface 786 of a workpiece to be cut. The suction cup dustextractor becomes attached to the surface due to the suction forcecrated by the vacuum cleaner in the suction chamber 38. The pivotalcover 724 is moved to its second position, extending away from collar 12(see FIG. 28 ). The drill bit 788 of a hammer drill is passed throughthe drill passage 18 of the collar 12 to engage with the surface 786 ofthe work piece to be cut, passing through the circular brush 772 as itdoes so. The hammer drill is activated in order to rotate and/or strikethe drill bit 788 to drill a hole in the work surface 786. Any dustgenerated during the drilling process is removed by the suction cup dustextractor and vacuum cleaner 782. The drill bit 788 is them removed fromthe hole in the surface 786 and the drill passage 18 of the collar 12.

The pivotal cover 724 is then moved to and locked in its first positionso that the pivotal cover 724 covers the upper entrance of the drillpassage 18 as shown in FIG. 29 . A pipe 780 from a high pressure airhose 790 of a high air pressure source 782, 792, 794 is then insertedthrough the hole 730 of the pivotal cover 724, through the drill passage18 and into the hole in the work surface 786. The conical shape of thehole 730 assists in guiding the pipe 780 through the hole 730 as well asproviding a seal between the washer 728 and the outer wall of the pipe780. A jet of high pressure air is then blasted through the pipe 780 andinto the hole in the surface 786. Any dust within the hole is forcefullyblown out of the hole and into the drill passage 18. The pivotal coverprevents this dust from exiting the drill passage 18 through upperentrance of the drill passage 18 and ensures that it is sucked into thesuction cup dust extractor by the vacuum cleaner 782 and then into thevacuum cleaner 782.

The high air pressure source can be a canister of compressed gas 792(see FIG. 32 b ), a powered compressor 794 (see FIG. 32 a ) or thevacuum cleaner 782 where the air expelled during the operation of thevacuum cleaner 782 is redirected back towards the suction cup compressorthrough the air hose 790 (see FIG. 32 c ).

The pipe 780 is then withdrawn from the collar 12 and the pivotal cover724 is moved to its second position where it extends away from thecollar 12. A brush 796 (see FIG. 32 d ) can then be inserted through thedrill passage 18 and into the hole in the work surface 786. The brush796 is reciprocatingly moved within the hole of the work piece to loosenany material attached to the wall of the hole.

The brush is then removed from the hole and the collar 12. The pivotalcover 724 is then moved again to and locked in its first position sothat the pivotal cover 724 covers the upper entrance of the drillpassage 18. The pipe 780 from the high pressure air hose 790 of a highair pressure source 782, 792, 794 is then reinserted through the hole732 of the pivotal cover 724, through the drill passage 18 and into thehole in the work surface 786. Another jet of high pressure air is thenblasted through the pipe 780 and into the hole. Any remaining dustwithin the hole is forcefully blown out of the hole and into the drillpassage 18, the pivotal cover 724 preventing this dust from exiting thedrill passage 18 through upper entrance of the drill passage 18 toensures that it is sucked into the suction cup dust extractor by thevacuum cleaner 782 and then into the vacuum cleaner 784.

A second embodiment of the present invention will now be described withreference to FIG. 31 . Where the same features are present in the secondembodiment are also present in the first embodiment described above, thesame reference numbers have been used. The design of the embodiment isthe same as the first embodiment except that the pivotal cover 724pivots about an axis 900 which extends in a direction parallel to thelongitudinal axis of the drill passage 18. The pivotal cover 724 canrotate in the direction of arrow T from a first position where it coversthe upper entrance to the drill passage 18 to an extended position(shown in dashed lines) remote from the upper entrance of the drillpassage 18. When the pivotal cover 724 is in its first position itlocates under the end of a flexible L shaped stop 902 which holds thepivotal cover 724 in its first position. The second embodiment operatesin the same manner as the first embodiment.

Referring to FIG. 30 , whilst the drill collars 24 of the first andsecond embodiments are described in relation to suction cup dustextractors, they can be used on different types of dust extractors suchas a dust extractor which mounts on a hammer drill.

FIG. 30 shows a hammer drill onto which a dust extract can be mounted(in the direction of Arrow M). Referring to FIG. 30 , a hammer drillcomprises a main housing 901 and a rear handle 904 attached to the mainhousing 901 via vibration dampeners 918 at its upper 906 and lower 908ends. The main housing 901 comprises a motor housing 912, in which ismounted an electric motor having an output spindle and a transmissionhousing 910, in which is mounted the hammer mechanism (not shown) androtary drive (not shown). A mode change knob 903 is used to change themode of operation of the hammer drill. A tool holder 914 is mounted onthe front of the transmission housing 910 which is capably of releasablyholding a cutting tool (not shown). The tool holder is cable of beingrotated about axis A. A front handle is attached to the transmissionhousing 910 behind the tool holder 914. A trigger switch 916 is mountedwithin the rear handle 904 by which an operator can activate the hammerdrill. An electric cable 920 connects to the base of the rear handle 904by which a mains AC electric power supply is supplied to the hammerdrill.

A typical dust extractor comprises a main housing 922 manufactured fromtwo plastic clam shells 924, 926 which are joined together about avertical plane using screws. The main housing 922 can clip onto themotor housing 912 of the hammer drill.

Mounted on the top of the main housing is a telescopic tubular extensionarm 928, 930. A first section 928 of the telescopic arm 930 can slide inand out of the other second section 930. A spring (not shown) biases thefirst section 928 out of the second section towards its maximum extendedposition.

Mounted on the end of the first section 928 remote from the main housingis a tubular support 934 and a collar 12. A drill passage 18 e is formedthrough the collar 122 to allow a cutting tool to pass through thecollar 12.

A dust collection box 936 releaseably connects to the front of the mainhousing 922. A filter (not shown) is mounted within the box 936. A fan(not shown) mounted in the housing 922 which is rotatably driven by amotor (not shown) to act as a vacuum source to draw air into the collarand through the dust collection box 936.

The new feature of the dust extractor described with reference to FIG.30 is the design of the collar 12. The collar 12 mounted on the dustextractor shown in FIG. 30 is the same design as the first embodimentdescribed above.

It will be appreciated by persons skilled in the art that the aboveembodiments have been described by way of example only and not in anylimitative sense, and that various alterations and modifications arepossible without departure from the scope of the invention as defined bythe appended claims.

Individual elements or features of a particular embodiment are generallynot limited to that particular embodiment, but, where applicable, areinterchangeable and can be used in a selected embodiment, even if notspecifically shown or described. The same may also be varied in manyways. Such variations are not to be regarded as a departure from thedisclosure, and all such modifications are intended to be includedwithin the scope of the disclosure.

Example embodiments are provided so that this disclosure will bethorough and will fully convey the scope to those who are skilled in theart. Numerous specific details are set forth such as examples ofspecific components, devices, and methods, to provide a thoroughunderstanding of embodiments of the present disclosure. It will beapparent to those skilled in the art that specific details need not beemployed, that example embodiments may be embodied in many differentforms and that neither should be construed to limit the scope of thedisclosure. In some example embodiments, well-known processes,well-known device structures, and well-known technologies are notdescribed in detail.

The terminology used herein is for the purpose of describing particularexample embodiments only and is not intended to be limiting. As usedherein, the singular forms “a,” “an,” and “the” may be intended toinclude the plural forms as well, unless the context clearly indicatesotherwise. The terms “comprises,” “comprising,” “including,” and“having,” are inclusive and therefore specify the presence of statedfeatures, integers, steps, operations, elements, and/or components, butdo not preclude the presence or addition of one or more other features,integers, steps, operations, elements, components, and/or groupsthereof. The method steps, processes, and operations described hereinare not to be construed as necessarily requiring their performance inthe particular order discussed or illustrated, unless specificallyidentified as an order of performance. It is also to be understood thatadditional or alternative steps may be employed.

1. A suction cup dust extractor for a drill comprising: a housing; adrill collar system attached to the housing, the drill collar systemincluding: a collar including a drill passage extending through thecollar and an extension forming an internal passage that connects at oneend with the drill passage, the extension being attachable to a housingof the dust extractor to enable the internal passage to connect to asuction passage of the dust extractor; and a cover mounted adjacent anentrance of the drill passage, the cover being moveable between a firstposition where it covers the entrance and a second position where isremote from the entrance, wherein the cover comprises at least hole thatpasses through the cover; a suction chamber formed by the walls of thehousing having an opening and which, in use, locates against a workpiece to create a chamber; at least one aperture located on the housingthrough which air can pass; at least one first air passage formed by thewalls of the housing that connects between the internal passage of thecollar and the at least one aperture to enable air to pass from theinternal passage to the at least one aperture; and at least one secondair passage formed within the housing that connects between the suctionchamber and the at least one single aperture to enable air to pass fromthe suction chamber to the at least one aperture.
 2. The suction cupdust extractor of claim 1, wherein the hole in a lengthwise direction isfrusto-conical in shape.
 3. The suction cup dust extractor of claim 1,wherein the cover comprises: a rigid outer ring sized to reset on thecollar in the first position; and a resiliently deformable washermounted inside of the outer ring.
 4. The suction cup dust extractor ofclaim 3, wherein the resiliently deformable washer has an inner sectionthrough which the hole extends and an outer section that surrounds theinner section and connects between the outer ring and the inner section.5. The suction cup dust extractor of claim 4, wherein a thickness of theinner section is approximately the same as that of the outer ring. 6.The suction cup dust extractor of claim 4, wherein a thickness of theouter section is less than that of the inner section.
 7. The suction cupdust extractor of claim 4, wherein the washer comprises plurality ofradial ribs formed on the surface of the outer section extending fromthe inner section radially outwardly to the outer ring.
 8. The suctioncup dust extractor of claim 4, wherein the inner section comprises aconical funnel attached to one side of the inner section which extendsthe length of the hole.
 9. The suction cup dust extractor of claim 1,wherein the cover pivots between its first position and its secondposition.
 10. The suction cup dust extractor of claim 1, wherein thecollar comprises a circular brush located adjacent the entrance of thedrill passage which extends radially inwardly.
 11. A dust extractor fora drill comprising: a housing having an engagement region for attachingto at least part of the housing of a drill; a drill collar systemattached to the housing, the drill collar system including: a collarincluding a drill passage extending through the collar and an extensionforming an internal passage that connects at one end with the drillpassage, the extension being attachable to a housing of the dustextractor to enable the internal passage to connect to a suction passageof the dust extractor; and a cover mounted adjacent an entrance of thedrill passage, the cover being moveable between a first position whereit covers the entrance and a second position where is remote from theentrance, wherein the cover comprises at least hole that passes throughthe cover; and at least one air passage formed by the walls of thehousing that connects between the internal passage of the collar and avacuum source to enable air to pass from the internal passage to thevacuum source.
 12. The dust extractor of claim 11, wherein the vacuumsource comprises a rotating fan mounted within the housing.
 13. The dustextractor of claim 11, wherein collar is connected to the housing usinga telescopic arm, the collar being mounted on one end of the arm, theother end of the arm being connected to the housing.
 14. The dustextractor of claim 11, comprising a dust collection box having a filtermounted on the housing, the at least one air passage passing through thedust collection box.
 15. The dust extractor of claim 11, wherein thehole in a lengthwise direction is frusto-conical in shape.
 16. The dustextractor of claim 11, wherein the cover comprises: a rigid outer ringsized to reset on the collar in the first position; and a resilientlydeformable washer mounted inside of the outer ring.
 17. The dustextractor of claim 16, wherein the resiliently deformable washer has aninner section through which the hole extends and an outer section thatsurrounds the inner section and connects between the outer ring and theinner section.
 18. The dust extractor of claim 17, wherein a thicknessof the inner section is approximately the same as that of the outerring, and a thickness of the outer section is less than that of theinner section.
 19. The dust extractor of claim 11, wherein the coverpivots between its first position and its second position.
 20. The dustextractor of claim 11, wherein the collar comprises a circular brushlocated adjacent the entrance of the drill passage which extendsradially inwardly.